The invention relates to a fuel injection valve for internal combustion engines, including a valve member, which is displaceable in a valve body counter to the restoring force of a valve spring and has a valve sealing face, which cooperates with a valve seat disposed on the valve body, and having a plurality of injection ports, disposed below the valve seat in the valve body, whose inlet openings are rounded.
One such fuel injection valve for an internal combustion engine is disclosed for instance in European Patent Disclosure EP 0 370 659 A1. The roundness of the inlet openings of the injection ports makes it possible for a larger quantity of fuel to be injected through the injection ports into the combustion chamber of the engine, because no constriction of the fuel flowing through the injection ports occurs as would result if the inlet opening had a sharp edge.
Also as a result of the rounded curved inlet openings, the shape of the stream ejected through the injection ports can be varied. In the fuel injection valve known from EP 0 370 659 A1, it is provided in this respect that the injection ports, on their side toward the valve member, have a different degree of roundness than on their side remote from the valve member.
Here and below, the term degree of roundness is understood to mean the radius of the rounded curved feature. A high degree of roundness means a rounded feature with a large radius, and a low degree of roundness means a rounded feature with a small radius.
The degrees of roundness of the inlet opening of the injection port of the fuel injection valve disclosed by EP 0 370 659 A1 are selected such that the most optimal possible combustion in the combustion chamber can be attained.
If--as is usual today--a plurality of injection ports are provided in the fuel injection valve, then fixed, predetermined injection ports and the resultant shapes of the stream of ejected fuel may not be very advantageous, depending on the installation position in the combustion chamber of an internal combustion engine.